DSpace Community:http://hdl.handle.net/2117/3656
Tue, 03 Mar 2015 22:51:37 GMT2015-03-03T22:51:37Zwebmaster.bupc@upc.eduUniversitat Politècnica de Catalunya. Servei de Biblioteques i DocumentaciónoGood Practice Guide for calibrating a hydrophone "in situ" with a non-omnidirectional source at 10 kHz (26-34)http://hdl.handle.net/2117/26515
Title: Good Practice Guide for calibrating a hydrophone "in situ" with a non-omnidirectional source at 10 kHz (26-34)
Authors: Garcia Benadí, Albert; Cadena Muñoz, Javier; Río Fernandez, Joaquín del; Roset Juan, Francesc Xavier; Manuel Lázaro, Antonio
Abstract: The aim of this paper is to provide the basis for the calibration of a hydrophone "in situ" with a non-omnidirectional source at 10 kHz, thus assigning a value of uncertainty, which may be high, but according to requirements, may be sufficientWed, 25 Feb 2015 15:59:59 GMThttp://hdl.handle.net/2117/265152015-02-25T15:59:59ZGarcia Benadí, Albert; Cadena Muñoz, Javier; Río Fernandez, Joaquín del; Roset Juan, Francesc Xavier; Manuel Lázaro, AntonionoThe aim of this paper is to provide the basis for the calibration of a hydrophone "in situ" with a non-omnidirectional source at 10 kHz, thus assigning a value of uncertainty, which may be high, but according to requirements, may be sufficientOtolith shape classification for fish stock discriminationhttp://hdl.handle.net/2117/26504
Title: Otolith shape classification for fish stock discrimination
Authors: Soria Pérez, José Antonio; Nasreddine, Kamal; Parisi Baradad, Vicenç; Ferrer Arnau, Luis Jorge; Benzinou, Abdesslam
Abstract: The shape analysis of otoliths, which are calcified
structures in the inner ear of teleostean fishes, is known to be
particularly relevant to address species identification and stock
discrimination. Generally, scientists use classical methodologies
of statistical analysis and shape recognition such as Fourier
shape descriptors and Principal Component Analysis (PCA).
These methods are subject to several limitations mainly to their
incapacity to locate irregularities because they are based on global
characterization of shape. Recently, more advanced techniques
are proposed in this context in order to improve classification
accuracies. The first recent method exploits the potential of shape
geodesics which rely on local shape features for classification
issues. The second one addresses the Best-Basis paradigm which
combines the Wavelet Transform, and the potential of statistical
analysis in order to fully automate the selection process of efficient
features for classification. These methods have been shown to
significantly outperform the standard approaches but they are not
compared together yet. This study compare these two methods on
a real dataset. The comparison is performed on
600
striped red
mullet calcified structures collected for the NESPMAN European
project. For each method, performances are reported for the
classification of samples coming from three geographical zones
in the Northwest European seas: the Bay of Biscay, a mixing zone
composed of the Celtic Sea and the Western English Channel and
a northern zone composed of the Eastern English Channel and
the North Sea. Comparison shows that both methods lead to same
conclusions.http://hdl.handle.net/2117/26504Soria Pérez, José Antonio; Nasreddine, Kamal; Parisi Baradad, Vicenç; Ferrer Arnau, Luis Jorge; Benzinou, AbdesslamnoAccuracy, Aquaculture, Biology, Europe, Feature extraction, Robustness, ShapeThe shape analysis of otoliths, which are calcified
structures in the inner ear of teleostean fishes, is known to be
particularly relevant to address species identification and stock
discrimination. Generally, scientists use classical methodologies
of statistical analysis and shape recognition such as Fourier
shape descriptors and Principal Component Analysis (PCA).
These methods are subject to several limitations mainly to their
incapacity to locate irregularities because they are based on global
characterization of shape. Recently, more advanced techniques
are proposed in this context in order to improve classification
accuracies. The first recent method exploits the potential of shape
geodesics which rely on local shape features for classification
issues. The second one addresses the Best-Basis paradigm which
combines the Wavelet Transform, and the potential of statistical
analysis in order to fully automate the selection process of efficient
features for classification. These methods have been shown to
significantly outperform the standard approaches but they are not
compared together yet. This study compare these two methods on
a real dataset. The comparison is performed on
600
striped red
mullet calcified structures collected for the NESPMAN European
project. For each method, performances are reported for the
classification of samples coming from three geographical zones
in the Northwest European seas: the Bay of Biscay, a mixing zone
composed of the Celtic Sea and the Western English Channel and
a northern zone composed of the Eastern English Channel and
the North Sea. Comparison shows that both methods lead to same
conclusions.Objectives of the NeXOS project in developing next generation ocean sensor systems for a more cost-efficient assessment of ocean waters and ecosystems, and fisheries managementhttp://hdl.handle.net/2117/26265
Title: Objectives of the NeXOS project in developing next generation ocean sensor systems for a more cost-efficient assessment of ocean waters and ecosystems, and fisheries management
Authors: Delory, Eric; Castro, Ayoze; Waldmann, Christoph; Rolin, Jean-François; Woerther, Patrice; Gille, J.; Río Fernandez, Joaquín del; Zielinski, O.; Golmen, L.; Hareide, N. R.; Pearlman, Jay S; Garello, R.
Abstract: The NeXOS project aims to develop new multifunctional sensor systems supporting a number of scientific, technical and societal objectives, ranging from more precise monitoring and modelling of the marine environment to an improved management of fisheries. Several sensors will be developed, based on optical and passive acoustics technologies, addressing key environmental descriptors identified by the European Marine Strategy Framework Directive (MSFD) for Good Environmental Status (GES). Two of the new sensors will also contribute to the European Union Common Fisheries Policy (CFP), with a focus on variables of interest to an Ecosystem Approach to Fisheries (EAF). An objective is the improved cost-efficiency, from procurement to operations, via the implementation of several innovations, such as multiplatform integration, greater reliability through better antifouling management, greater sensor and data interoperability and the creation of market opportunities for European enterprises. Requirements will be further analysed for each new sensor system during the first phase of the project. Those will then be translated into engineering specifications, leading to the development phase. Sensors will then be tested, calibrated, integrated on several platform types, scientifically validated and demonstrated in the field. Translation to production and broad adoption are facilitated by participating industry. Overall, the paper presents an overview of the project objectives and plans for the next four years.Mon, 09 Feb 2015 12:49:46 GMThttp://hdl.handle.net/2117/262652015-02-09T12:49:46ZDelory, Eric; Castro, Ayoze; Waldmann, Christoph; Rolin, Jean-François; Woerther, Patrice; Gille, J.; Río Fernandez, Joaquín del; Zielinski, O.; Golmen, L.; Hareide, N. R.; Pearlman, Jay S; Garello, R.noAcoustics, Biogeochemistry, Compactness, Cost-efficiency, Fisheries management, GOOS, Hydrophones, Interoperability, Marine GEOSS, Multifunctional ocean sensors, Optical sensors, Polycyclic Aromatic Hydrocarbons, RECOPESCA, Sensor Web, Smart interface, Underwater soundThe NeXOS project aims to develop new multifunctional sensor systems supporting a number of scientific, technical and societal objectives, ranging from more precise monitoring and modelling of the marine environment to an improved management of fisheries. Several sensors will be developed, based on optical and passive acoustics technologies, addressing key environmental descriptors identified by the European Marine Strategy Framework Directive (MSFD) for Good Environmental Status (GES). Two of the new sensors will also contribute to the European Union Common Fisheries Policy (CFP), with a focus on variables of interest to an Ecosystem Approach to Fisheries (EAF). An objective is the improved cost-efficiency, from procurement to operations, via the implementation of several innovations, such as multiplatform integration, greater reliability through better antifouling management, greater sensor and data interoperability and the creation of market opportunities for European enterprises. Requirements will be further analysed for each new sensor system during the first phase of the project. Those will then be translated into engineering specifications, leading to the development phase. Sensors will then be tested, calibrated, integrated on several platform types, scientifically validated and demonstrated in the field. Translation to production and broad adoption are facilitated by participating industry. Overall, the paper presents an overview of the project objectives and plans for the next four years.NeXOS development plans in ocean optics, acoustics and observing systems interoperabilityhttp://hdl.handle.net/2117/26092
Title: NeXOS development plans in ocean optics, acoustics and observing systems interoperability
Authors: Delory, Eric; Castro, Ayoze; Waldmann, Christoph; Rolin, Jean-François; Woerther, Patrice; Gille, J.; Río Fernandez, Joaquín del; Zielinski, O.; Golmen, L.; Hareide, N. R.; Pearlman, Jay S
Abstract: A growing concern about the health of the world
oceans resulting from multiple stressors as for instance effects of
climate change and increasing offshore activities leads to the need
of better observational tools and strategies. The objective of the
NeXOS project is to serve those needs by developing new costeffective,
innovative and compact integrated multifunctional
sensor systems for ocean optics, ocean passive acoustics, and an
Ecosystem Approach to Fisheries (EAF), which can be deployed
from mobile and fixed ocean observing platforms, as well as to
develop downstream services for the Global Ocean Observing
System, Good Environmental Status of European marine waters
and the Common Fisheries Policy.Tue, 27 Jan 2015 10:46:36 GMThttp://hdl.handle.net/2117/260922015-01-27T10:46:36ZDelory, Eric; Castro, Ayoze; Waldmann, Christoph; Rolin, Jean-François; Woerther, Patrice; Gille, J.; Río Fernandez, Joaquín del; Zielinski, O.; Golmen, L.; Hareide, N. R.; Pearlman, Jay SnoMultifunctional ocean sensors, Compactness, Costefficiency, Interoperability, Marine GEOSS, GOOS, Optical sensors, Biogeochemistry, Polycyclic Aromatic Hydrocarbons, Underwater sound, Hydrophones, Acoustics, Fisheries management, RECOPESCA, Smart interface, Sensor WebA growing concern about the health of the world
oceans resulting from multiple stressors as for instance effects of
climate change and increasing offshore activities leads to the need
of better observational tools and strategies. The objective of the
NeXOS project is to serve those needs by developing new costeffective,
innovative and compact integrated multifunctional
sensor systems for ocean optics, ocean passive acoustics, and an
Ecosystem Approach to Fisheries (EAF), which can be deployed
from mobile and fixed ocean observing platforms, as well as to
develop downstream services for the Global Ocean Observing
System, Good Environmental Status of European marine waters
and the Common Fisheries Policy.Smart electronic interface for web enabled ocean sensor systemshttp://hdl.handle.net/2117/26040
Title: Smart electronic interface for web enabled ocean sensor systems
Authors: Toma, Daniel; Río Fernandez, Joaquín del; Jirka, Simon; Delory, Eric; Pearlman, Jay S
Abstract: The objective of the European FP7 project NeXOS
(Next generation Low-Cost Multifunctional Web Enabled Ocean
Sensor Systems Empowering Marine, Maritime and Fisheries
Management) is to develop cost-efficient innovative and
interoperable in-situ sensors deployable from multiple platforms
to support the development of a truly integrated Ocean
Observing System. Therefore, several sensor systems will be
developed in NeXOS project for specific technologies and
monitoring strategies such as: ocean passive acoustics, ocean
optics, and EAF monitoring (Ecosystem Approach to Fisheries),
that will provide an integrated, technologically coherent system
for multi-scale, multi-parameter monitoring of the oceans. For all
these sensors system, NeXOS will develop the Smart Electronic
Interface for Sensors and Instruments (SEISI) which is a set of
standards and functionalities to enable Web-based sharing,
discovery, exchange and processing of sensor observations, and
operation of sensor systems. The architecture will satisfy
international standards, defined by ISO, OGC, and the INSPIRE
directive, to enable integration of marine sensors with existing
observing systems. The SEISI will provide a multifunctional
interface for many types of current sensors and instruments as
well as the new multi-parameter sensor systems, and a standard
interface for existing observing systems platforms such as: cabled
observatories, buoys, gliders or Ferryboxes on ship or vessel of
opportunity. To achieve the compatibility with all these
platforms, the sensor systems developed in NeXOS based on
SEISI will be designed to accomplish two main requirements of
these platforms regarding the communication bandwidth and the
power consumption.Fri, 23 Jan 2015 09:07:03 GMThttp://hdl.handle.net/2117/260402015-01-23T09:07:03ZToma, Daniel; Río Fernandez, Joaquín del; Jirka, Simon; Delory, Eric; Pearlman, Jay SnoMultifunctional ocean sensors, Interoperability, OGC, Standards, SensorMLThe objective of the European FP7 project NeXOS
(Next generation Low-Cost Multifunctional Web Enabled Ocean
Sensor Systems Empowering Marine, Maritime and Fisheries
Management) is to develop cost-efficient innovative and
interoperable in-situ sensors deployable from multiple platforms
to support the development of a truly integrated Ocean
Observing System. Therefore, several sensor systems will be
developed in NeXOS project for specific technologies and
monitoring strategies such as: ocean passive acoustics, ocean
optics, and EAF monitoring (Ecosystem Approach to Fisheries),
that will provide an integrated, technologically coherent system
for multi-scale, multi-parameter monitoring of the oceans. For all
these sensors system, NeXOS will develop the Smart Electronic
Interface for Sensors and Instruments (SEISI) which is a set of
standards and functionalities to enable Web-based sharing,
discovery, exchange and processing of sensor observations, and
operation of sensor systems. The architecture will satisfy
international standards, defined by ISO, OGC, and the INSPIRE
directive, to enable integration of marine sensors with existing
observing systems. The SEISI will provide a multifunctional
interface for many types of current sensors and instruments as
well as the new multi-parameter sensor systems, and a standard
interface for existing observing systems platforms such as: cabled
observatories, buoys, gliders or Ferryboxes on ship or vessel of
opportunity. To achieve the compatibility with all these
platforms, the sensor systems developed in NeXOS based on
SEISI will be designed to accomplish two main requirements of
these platforms regarding the communication bandwidth and the
power consumption.Intelligent sensors : Why they are so important for future ocean observing systemshttp://hdl.handle.net/2117/26039
Title: Intelligent sensors : Why they are so important for future ocean observing systems
Authors: Waldmann, Christoph; Río Fernandez, Joaquín del; Toma, Daniel; O'Reilly, Thomas C.; Pearlman, Jay S
Abstract: The complexity of installations in the oceans to
carry out observations on specific processes and for detecting
long-term trends have grown significantly in the past years. This
applies also to the type and number of sensors that are in use in
observing systems. In these days, sensors shall be compatible to
different platforms that are in use like floats, gliders or moorings,
and accordingly also different data acquisition systems.
Facilitating the integration process in existing or newly
established observing systems comes with a real benefit for the
operators and is important for the broader application of
different sensors. However, how to achieve the goals is under
debate. The most serious obstacle for all initiatives is the
willingness of stakeholders to adopt a strategy and, even more so,
to adopt a specific architecture to enable interoperability across
platforms and observing systems. Therefore, the situation at this
point in time is characterized by the fact that parallel approaches
have been developed (IEEE 1451, the OGC set of standards, etc.)
that are ready to be evaluated but still lacking the support by the
community. Therefore it seems to be a good time to consider and
to agree on the implementation of interoperability arrangements.Fri, 23 Jan 2015 08:12:50 GMThttp://hdl.handle.net/2117/260392015-01-23T08:12:50ZWaldmann, Christoph; Río Fernandez, Joaquín del; Toma, Daniel; O'Reilly, Thomas C.; Pearlman, Jay SnoInteroperability, Standards, Protocols, Data formats, Sensors, Instruments, Ocean observing system, ObservatoriesThe complexity of installations in the oceans to
carry out observations on specific processes and for detecting
long-term trends have grown significantly in the past years. This
applies also to the type and number of sensors that are in use in
observing systems. In these days, sensors shall be compatible to
different platforms that are in use like floats, gliders or moorings,
and accordingly also different data acquisition systems.
Facilitating the integration process in existing or newly
established observing systems comes with a real benefit for the
operators and is important for the broader application of
different sensors. However, how to achieve the goals is under
debate. The most serious obstacle for all initiatives is the
willingness of stakeholders to adopt a strategy and, even more so,
to adopt a specific architecture to enable interoperability across
platforms and observing systems. Therefore, the situation at this
point in time is characterized by the fact that parallel approaches
have been developed (IEEE 1451, the OGC set of standards, etc.)
that are ready to be evaluated but still lacking the support by the
community. Therefore it seems to be a good time to consider and
to agree on the implementation of interoperability arrangements.Underwater acoustic communication messaging time stamp applied to global time synchronizationhttp://hdl.handle.net/2117/26013
Title: Underwater acoustic communication messaging time stamp applied to global time synchronization
Authors: Pallarés Valls, Oriol; Río Fernandez, Joaquín del; Bouvet, Pierre-Jean
Abstract: This paper presents a new approach to time stamp
messages in underwater acoustic communication. Message time
stamping is a widely used method for synchronizing two clocks
over a cabled or wireless communication, by exchanging time
information in pilot messages. In this work we use a National
Instruments Field-Programmable Gate Array (FPGA) for
performing deterministic hardware time stamp of windowed
acquired data, and then we apply a software detection of frame
information inside this acquisition window. Frame time stamp
in conjunction with global time reference enclosed in the message,
provide enough information for achieving synchronization
accuracy between two clocks below few microseconds.Wed, 21 Jan 2015 13:03:03 GMThttp://hdl.handle.net/2117/260132015-01-21T13:03:03ZPallarés Valls, Oriol; Río Fernandez, Joaquín del; Bouvet, Pierre-JeannoAccuracy, Acoustics, Clocks, Field programmable gate arrays, Hardware, OFDM, SynchronizationThis paper presents a new approach to time stamp
messages in underwater acoustic communication. Message time
stamping is a widely used method for synchronizing two clocks
over a cabled or wireless communication, by exchanging time
information in pilot messages. In this work we use a National
Instruments Field-Programmable Gate Array (FPGA) for
performing deterministic hardware time stamp of windowed
acquired data, and then we apply a software detection of frame
information inside this acquisition window. Frame time stamp
in conjunction with global time reference enclosed in the message,
provide enough information for achieving synchronization
accuracy between two clocks below few microseconds.A Sensor web architecture for sharing oceanographic sensor datahttp://hdl.handle.net/2117/25969
Title: A Sensor web architecture for sharing oceanographic sensor data
Authors: Jirka, Simon; Toma, Daniel; Río Fernandez, Joaquín del; Delory, Eric
Abstract: This paper introduces the Sensor Web
architecture of the NeXOS project as example how interoperable
standards help, to facilitate the creation of an infrastructure for
sharing oceanographic observation data and the integration of
sensor data into applications. Important technological
foundations of the NeXOS Sensor Web architecture are the
concepts of spatial data infrastructures and the Sensor Web
Enablement framework of the Open Geospatial Consortium. As a
result an architecture concept has been developed, which is
introduced in this paper.Tue, 20 Jan 2015 15:59:06 GMThttp://hdl.handle.net/2117/259692015-01-20T15:59:06ZJirka, Simon; Toma, Daniel; Río Fernandez, Joaquín del; Delory, EricnoSensor Web, Sensor Observation Service, Ocean observatories, Observation data, Spatial data infrastructuresThis paper introduces the Sensor Web
architecture of the NeXOS project as example how interoperable
standards help, to facilitate the creation of an infrastructure for
sharing oceanographic observation data and the integration of
sensor data into applications. Important technological
foundations of the NeXOS Sensor Web architecture are the
concepts of spatial data infrastructures and the Sensor Web
Enablement framework of the Open Geospatial Consortium. As a
result an architecture concept has been developed, which is
introduced in this paper.Underwater potentiostat for real-time electrochemical corrosion measurementshttp://hdl.handle.net/2117/25968
Title: Underwater potentiostat for real-time electrochemical corrosion measurements
Authors: Masmitjà Rusiñol, Ivan; Río Fernandez, Joaquín del; Damborenea González, Juan José; Conde, A.
Abstract: Corrosion due to seawater studies are urgently required for a safe technology development. Some studies demonstrated that the corrosion rates for most alloys could be four times less than surface corrosion rates. A device for continuous electrochemical measuring of corrosion in real time and underwater is shown in this paper. Therefore, this equipment allows improving the knowledge about long-term materials behavior in this aggressive environment for the scientific community. Also, it has been designed to allow the connection to underwater observatories such as OBSEA.Tue, 20 Jan 2015 15:37:36 GMThttp://hdl.handle.net/2117/259682015-01-20T15:37:36ZMasmitjà Rusiñol, Ivan; Río Fernandez, Joaquín del; Damborenea González, Juan José; Conde, A.noPotentiostat, Corrosion, Electrochemical, Realtime, Corrosion, Current measurement, Electric potential, Electrodes, Observatories, Sea measurements, Voltage measurementCorrosion due to seawater studies are urgently required for a safe technology development. Some studies demonstrated that the corrosion rates for most alloys could be four times less than surface corrosion rates. A device for continuous electrochemical measuring of corrosion in real time and underwater is shown in this paper. Therefore, this equipment allows improving the knowledge about long-term materials behavior in this aggressive environment for the scientific community. Also, it has been designed to allow the connection to underwater observatories such as OBSEA.Small instrument to volcanic seismic signalshttp://hdl.handle.net/2117/25520
Title: Small instrument to volcanic seismic signals
Authors: Manuel Lázaro, Antonio; Carreras Pons, Normandino; Gomáriz Castro, SpartacusWed, 14 Jan 2015 17:08:29 GMThttp://hdl.handle.net/2117/255202015-01-14T17:08:29ZManuel Lázaro, Antonio; Carreras Pons, Normandino; Gomáriz Castro, SpartacusnoAutomated data quality assurance using OGC sensor web enablement frameworks for marine observatorieshttp://hdl.handle.net/2117/24770
Title: Automated data quality assurance using OGC sensor web enablement frameworks for marine observatories
Authors: Manuel Lázaro, Antonio; Carreras Pons, Normandino; Bghiel, Ikram; Hidalgo Castro, Alberto; Río Fernandez, Joaquín del; Toma, DanielWed, 19 Nov 2014 15:39:41 GMThttp://hdl.handle.net/2117/247702014-11-19T15:39:41ZManuel Lázaro, Antonio; Carreras Pons, Normandino; Bghiel, Ikram; Hidalgo Castro, Alberto; Río Fernandez, Joaquín del; Toma, DanielnoImplementation on MicroBlaze of AES algorithm to reveal fake keys against side-channel attackshttp://hdl.handle.net/2117/24664
Title: Implementation on MicroBlaze of AES algorithm to reveal fake keys against side-channel attacks
Authors: Lumbiarres López, Rubén; López García, Mariano; Canto Navarro, Enrique Fernando
Abstract: This paper presents a new proposal for hiding the cryptographic key, when the so-called side-channel attacks (SCAs) are applied to break the security of AES-128. The algorithm was executed on MicroBlaze, but the proposed method is generic and can be extended to any other microprocessor. SCAs are based on examining the correlation produced between the data and operations performed by the microprocessor and its actual power consumption. Traditionally, such weakness is counteracted by introducing countermeasures addressed to reduce as much as possible this correlation, making data and power consumption independent. On the contrary, the proposal presented in this paper introduces some modifications in the AES algorithm. These changes aim at concealing the true key by reinforcing the correlation coefficient in such a way that a classical attack leads to a false key. This way, the system misleads the attacker and apparently behaves as an unprotected system that, in fact, reveals a false positive. The complete system was built on a Virtex-5 FPGA. Experimental results show the strength of our implementation, which is capable of successfully hiding the true cryptographic key.Tue, 11 Nov 2014 07:50:47 GMThttp://hdl.handle.net/2117/246642014-11-11T07:50:47ZLumbiarres López, Rubén; López García, Mariano; Canto Navarro, Enrique FernandonoCryptography. FPGAs applications, MicroBlaze, Side-channel attacksThis paper presents a new proposal for hiding the cryptographic key, when the so-called side-channel attacks (SCAs) are applied to break the security of AES-128. The algorithm was executed on MicroBlaze, but the proposed method is generic and can be extended to any other microprocessor. SCAs are based on examining the correlation produced between the data and operations performed by the microprocessor and its actual power consumption. Traditionally, such weakness is counteracted by introducing countermeasures addressed to reduce as much as possible this correlation, making data and power consumption independent. On the contrary, the proposal presented in this paper introduces some modifications in the AES algorithm. These changes aim at concealing the true key by reinforcing the correlation coefficient in such a way that a classical attack leads to a false key. This way, the system misleads the attacker and apparently behaves as an unprotected system that, in fact, reveals a false positive. The complete system was built on a Virtex-5 FPGA. Experimental results show the strength of our implementation, which is capable of successfully hiding the true cryptographic key.Buoyancy model for Guanay II AUVhttp://hdl.handle.net/2117/24443
Title: Buoyancy model for Guanay II AUV
Authors: Masmitjà Rusiñol, Ivan; González Agudelo, Julián; Gomáriz Castro, Spartacus
Abstract: The AUV Guanay II is a vehicle developed by
SARTI research group of Universitat Politècnica de Catalunya with the objective of providing a platform for measuring
oceanographic variables, such as the temperature and salinity of the water column. In the vertical dive is important not to disturb the environment to avoid influencing in the measurements. For
this reason a variable buoyancy (VB) system to do the vertical immersions has been designed. This paper presents the model
designed to change the buoyancy of the vehicle and the tests both laboratory and field.Wed, 22 Oct 2014 09:15:25 GMThttp://hdl.handle.net/2117/244432014-10-22T09:15:25ZMasmitjà Rusiñol, Ivan; González Agudelo, Julián; Gomáriz Castro, SpartacusnoThe AUV Guanay II is a vehicle developed by
SARTI research group of Universitat Politècnica de Catalunya with the objective of providing a platform for measuring
oceanographic variables, such as the temperature and salinity of the water column. In the vertical dive is important not to disturb the environment to avoid influencing in the measurements. For
this reason a variable buoyancy (VB) system to do the vertical immersions has been designed. This paper presents the model
designed to change the buoyancy of the vehicle and the tests both laboratory and field.Hybrid time synchronization for Underwater Sensor Networkshttp://hdl.handle.net/2117/24186
Title: Hybrid time synchronization for Underwater Sensor Networks
Authors: Pallarés Valls, Oriol; Bouvet, Pierre-Jean; Río Fernandez, Joaquín del
Abstract: Time synchronization is an important part of distributed applications over a sensor network. In this work we investigate time synchronization problems over a shallow UWSN, taking into account all main communication challenges of the water channel and observing its behavior in simulation and real tests. It is proposed an hybrid frame based time sinchronization using both, LFM and OFDM communication with channel impulse response equalization. Simulation results show how Hybrid synchronization outperforms existing synchronization protocols and how these results sults are affected in real water tests.Tue, 30 Sep 2014 10:27:15 GMThttp://hdl.handle.net/2117/241862014-09-30T10:27:15ZPallarés Valls, Oriol; Bouvet, Pierre-Jean; Río Fernandez, Joaquín delnoTime synchronization is an important part of distributed applications over a sensor network. In this work we investigate time synchronization problems over a shallow UWSN, taking into account all main communication challenges of the water channel and observing its behavior in simulation and real tests. It is proposed an hybrid frame based time sinchronization using both, LFM and OFDM communication with channel impulse response equalization. Simulation results show how Hybrid synchronization outperforms existing synchronization protocols and how these results sults are affected in real water tests.Experimental validation and modeling of plucked piezoelectric for underwater energy harvesting systemhttp://hdl.handle.net/2117/24184
Title: Experimental validation and modeling of plucked piezoelectric for underwater energy harvesting system
Authors: Toma, Daniel Mihai; Río Fernandez, Joaquín del; Carbonell Ventura, Montserrat; Bernet Piquet, Ferran; Miquel Masalles, Jaume
Abstract: Underwater wireless sensing systems are envisioned for stand-alone applications and as an addition to cabled observatory systems such as the OBSEA marine observatory. Therefore, this work presents a solution on how to generate power for marine wireless sensors using underwater motion energy. In this pare it is described a prototype based on a Bristol cylinder which can generate electrical voltage using piezoelectric bimorphs. Collecting water motion energy using piezoelectric energy harvesting is particularly difficult due to the mismatch between the low frequency of water kinetics and the high-frequency requirements of piezoelectric transducers. Therefore, to achieve frequency up-conversion we propose the use of the plucking technique applied to propose the use of the plucking technique applied to piezoelectric energy harvester. Experimental results show that the proposed energy harvester achieves a maximum power density of 350µW/cm3.Tue, 30 Sep 2014 09:05:40 GMThttp://hdl.handle.net/2117/241842014-09-30T09:05:40ZToma, Daniel Mihai; Río Fernandez, Joaquín del; Carbonell Ventura, Montserrat; Bernet Piquet, Ferran; Miquel Masalles, JaumenoUnderwater wireless sensing systems are envisioned for stand-alone applications and as an addition to cabled observatory systems such as the OBSEA marine observatory. Therefore, this work presents a solution on how to generate power for marine wireless sensors using underwater motion energy. In this pare it is described a prototype based on a Bristol cylinder which can generate electrical voltage using piezoelectric bimorphs. Collecting water motion energy using piezoelectric energy harvesting is particularly difficult due to the mismatch between the low frequency of water kinetics and the high-frequency requirements of piezoelectric transducers. Therefore, to achieve frequency up-conversion we propose the use of the plucking technique applied to propose the use of the plucking technique applied to piezoelectric energy harvester. Experimental results show that the proposed energy harvester achieves a maximum power density of 350µW/cm3.